Use of Activated Carbon in Conjunction with other Separations

USE OF ACTIVATED CARBON IN CONJUNCTION WITH OTHER SEPARATIONS 

Thus far we have discussed activated carbon acting as an agent of and by itself. More often it functions as a partner in a process, allied and associated with one or more other means of separation.1,2,3 In such combinations, the characteristics of the system involved and the objectives to be accomplished will govern the role of each cooperating means of separation. Each method may do that part for which it is best qualified several partners may operate collectively to attain a degree of purification that could not be accomplished by 

The assistance furnished to or by associated treatments ranges in significance and magnitude. On occasion much benefit may be derived from a very simple auxiliary treatment e.g., many operations have been aided by pre-filtration through diatomaceous earth to remove slimes that would otherwise coat the surface of the carbon and diminish the adsorptive capacity. In contrast are the specialized and elaborate techniques employed in some biological separations. Let us briefly review types of auxiliary aid and associated procedures. 

In many operations the material to be purified is received as a liquid or in solution and is processed as is. Modification may be needed as with a high viscosity liquid that may require dilution with a miscible solvent. 

and similar solids are usually treated at a temperature sufficiently high to convert them to a fluid state, although on occasion a fluid state is effected by dissolving the substance in a suitable solvent. This is done when it is desirable to minimize losses of a costly fat or wax by retention also when it is desired to conduct an adsorption at temperatures below the melting point of the solid material being purifled. 

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